topology: Set capacity_freq_ref in all cases

If "capacity-dmips-mhz" is not set, raw_capacity is null and we skip the
normalization step which includes setting per_cpu capacity_freq_ref.
Always register the notifier but skip the capacity normalization if
raw_capacity is null.

Fixes: 9942cb22 ("sched/topology: Add a new arch_scale_freq_ref() method")
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Pierre Gondois <pierre.gondois@arm.com>
Tested-by: Mark Brown <broonie@kernel.org>
Tested-by: Paul Barker <paul.barker.ct@bp.renesas.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lore.kernel.org/r/20240117190545.596057-1-vincent.guittot@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/base/arch_topology.c

@@ -431,9 +431,6 @@ init_cpu_capacity_callback(struct notifier_block *nb,
 	struct cpufreq_policy *policy = data;
 	int cpu;
 
-	if (!raw_capacity)
-		return 0;
-
 	if (val != CPUFREQ_CREATE_POLICY)
 		return 0;
 
@@ -450,9 +447,11 @@ init_cpu_capacity_callback(struct notifier_block *nb,
 	}
 
 	if (cpumask_empty(cpus_to_visit)) {
-		topology_normalize_cpu_scale();
-		schedule_work(&update_topology_flags_work);
-		free_raw_capacity();
+		if (raw_capacity) {
+			topology_normalize_cpu_scale();
+			schedule_work(&update_topology_flags_work);
+			free_raw_capacity();
+		}
 		pr_debug("cpu_capacity: parsing done\n");
 		schedule_work(&parsing_done_work);
 	}
@@ -472,7 +471,7 @@ static int __init register_cpufreq_notifier(void)
 	 * On ACPI-based systems skip registering cpufreq notifier as cpufreq
 	 * information is not needed for cpu capacity initialization.
 	 */
-	if (!acpi_disabled || !raw_capacity)
+	if (!acpi_disabled)
 		return -EINVAL;
 
 	if (!alloc_cpumask_var(&cpus_to_visit, GFP_KERNEL))